A practical guide for optical and production engineers: the five criteria for choosing a light-absorbing anti-reflection material for stray light control, why black paint and black anodizing often fall short in the near-infrared, and how the three FINESHUT grades compare from 550 to 1500 nm.

We lined half of an inexpensive mount adapter with FINESHUT KIWAMI and compared reflections and test shots in direct sunlight.

FINESHUT and IR Flock Sheet absorb from visible to near-infrared, come with adhesive backing, and can be laser-cut to your drawing.

Black clothing and black anodizing can look perfectly black and still reflect near-infrared light. NIR camera photos and measured reflectance show which materials absorb NIR.

A material that looks black to the eye can be bright to a near-infrared sensor. Based on our paper in the Journal of the Japan Society of Infrared Science and Technology, here are three ways to build absorbers that work from the visible range into the NIR, with measured data.

Tokyo Polytechnic University’s robot club, Karakuri Kobo, introduced a stealth advantage in the All-Japan Robot Sumo Tournament by using Fineshut KIWAMI, an advanced infrared-absorbing sheet. By reducing detection from infrared sensors, the material showcased new possibilities in competitive robotics. Although the team competed in the 500g autonomous class without advancing to nationals, their innovative use of stealth technology highlights the future of robot sumo and advanced materials.

We compared four commonly available black papers: Plike Black, NT Rasha Shikkoku, OK AC Card Makuro, and Daiso Black Colored Drawing Paper. NT Rasha Shikkoku measured darkest at 3.35% average visible reflectance, against 6.02% for the Daiso paper. We also put it side by side with our own Fineshut SP.

We visited JAXA's Sagamihara Campus to see how Fineshut KIWAMI is helping a historic rooftop telescope cope with urban stray light, and how that work connects to Japan's JASMINE infrared satellite project.

Fineshut KIWAMI and Musou Black Paint are suppressing stray light inside the visible-light cameras of Japanese astronomical telescopes, helping researchers observe faint objects like Mira variable stars and supernovae.